CHAPTER XXI. 



THE LOACH. 



THE Loach (Colitis barbatus), sometimes termed stone loach, from its 

 habit of burrowing under stones, and beardie, from the barbules at its 

 mouth varying from six to ten is a little gudgeon-like fish inhabiting 

 most of our sharp rills and streams. Like the minnow, it is rarely found 

 in deep parts, but frequents the shallower spots of the stream, where a 

 constant change of water is one of the chief features. From careful experi- 

 ments I am led to the conclusion that the sight of the loach is not greatly 

 developed, but I have no doubt that its sense of sound and touch are 

 exquisitely sensitive. Like all ground fish, also, such as barbel, gudgeon, 

 carp, eels, and chub, it is very susceptible of electrical impressions. 

 The agitation of one of these fish in an insulated glass globe of water 

 charged with electricity is painful to witness, and sufficiently declares 

 the fact. 



Perhaps the most remarkable feature of the loach consists in its 

 possessing an air bladder, inclosed in a bony capsule, behind the head. 

 The capsule is divided into two compartments ; the arrangement is 

 considered by Professor Owen to be subservient to the fish's perception 

 of sound. Its swimming movements, although sufficiently volatile when 

 made contiguous to the ground, are nevertheless awkward, and indeed 

 painful, when the effort is directed to attaining the surface of the water. 

 The fish spawns in April, and seems to be extraordinarily prolific. 



The loach is unconquerably shy, and, like some of the Indian mud fish, 

 delights in creating a muddy cloud around it whilst feeding. This fact 

 strengthens my idea that its sight is, from not being of great service in 

 searching for food, imperfectly developed. It is very voracious, and will 

 devour comparatively great quantities of worms and other insects. Its 

 teeth are numerous, and in one row only. I am of opinion that the fish 

 is not at all herbivorous, but entirely carnivorous. It is of considerable 



